인공 슬관절 전치환술 환자에서 신속동량 혈액희석요법

Abstract

Background: Acute normovolemic hemodilution (ANH) is an intraoperative blood management strategy. Benefits of ANH are the reduction of red blood cell loss and the shedding of whole blood perioperatively at lower hematocrit (Hct) levels. In this prospective, randomized, controlled trial we sought to evaluate the effectiveness of ANH in terms of decreasing the need for allogeneic transfusion after conventional unilateral total knee arthroplasty (TKA).

Methods: Between January 2012 and May 2012, 40 consecutive patients scheduled to undergo elective, primary, cemented, unilateral TKA for knee osteoarthritis were enrolled. Patients were randomized to either a study (AHN) group (n=20) (Group A) or a control group (n=20) (Group B). Units of allogeneic blood transfused, and the number of patients who required allogeneic transfusion were considered the primary outcomes. Hb and Hct blood values were measured on arrival in the operating room, 1 minute after tourniquet deflation, in the post-anesthesia care unit (PACU), and daily at the same time for 14 days postoperatively.

Results: In the ANH group, significantly (p<0.05) less allogeneic blood transfusion (6 units in Group A vs 15 units in Group B) was required after operation. Six patients, who required a transfusion in Group A received 1 unit of allogeneic blood. In contrast, 6 of 9 patients, who required transfusion in Group B, received at least 2 units of allogeneic blood. Hb and Hct values, measured 1 minute after tourniquet deflation and at PACU arrival, were significantly lower in Group A than in Group B, but no significant intergroup difference was found after reinfusion of autologous blood (e.g., 1 hour after arrival in the PACU). Hb and Hct values reached its lowest point at 3 days postoperatively regardless of the study group. There was no complication related to the methods of the protocol.

Conclusions: ANH is likely to reduce postoperative allogeneic transfusion requirement in patients undergoing unilateral TKA. Additional studies on adjunctive strategies are required to reduce allogeneic blood transfusion requirements.